How do i disable a tab, so that the user cannot change to it?

Question

I want to make a quiz, which goes through the questions, keeping in mind that while question 1 is being used, the others are disabled. Once the Next button is clicked it should change directly to Q2, disabling Q1 and so on.

How do I make it disable the previous tab and keep the current one enabled after the Next button is clicked?

Solution 1

A Tab can be accessed by its index, like so:

tabControl.TabPages[0]

So, say you're starting on tab 1 (index = 0), you want to disable all the other tabs.

// This can be done manually in the designer as well.
foreach(TabPage tab in tabControl.TabPages)
{
    tab.Enabled = false;
}
(tabControl.TabPages[0] as TabPage).Enabled = true;

Now, when you press the Next button, you want to disable the current tab, enable the next one, AND GO to the next one. But remember to check if the tab exists!

if(tabControl.TabCount - 1 == tabControl.SelectedIndex)
  return; // No more tabs to show!

tabControl.SelectedTab.Enabled = false;
var nextTab = tabControl.TabPages[tabControl.SelectedIndex+1] as TabPage;
nextTab.Enabled = true;
tabControl.SelectedTab = nextTab;

DISCLAIMER: This is not tested, but it should be something along these lines.

You stated that you got an error about object not containing a definition for Enabled - my code typecasts each tab page as a TabPage. However I have not tested it.

Solution 2

As stated previously tabs can be selected by index.

So as before, let's disable all other tabs:

foreach(TabPage tab in tabControl.TabPages)
{
    tab.Enabled = false;
}
(tabControl.TabPages[0] as TabPage).Enabled = true;

Now the way to prevent navigating to any other tab is simple:

private void tabControl_Selecting(object sender, TabControlCancelEventArgs e)
    {
        if (!e.TabPage.Enabled)
        {
            e.Cancel = true;
        }
    }

The only downside is that they will appear selectable, meaning they are not grayed out. You would have to do this yourself if you want the look to appear unavailable as well.

Solution 3

Another solution (the simplest I think) :

• Using a global variable (here currentSelectedTab)

• Using the event Selecting

    // currentSelectedTab is the Only Tab I want enabled.
    TabPage currentSelectedTab = tabWizardControl.TabPages[0];
  
    private void tabWizardControl_Selecting(object sender, TabControlCancelEventArgs e)
    {
        int selectedTab = tabWizardControl.SelectedIndex;
        //Disable the tab selection
        if (currentSelectedTab != selectedTab)
        {
            //If selected tab is different than the current one, re-select the current tab.
            //This disables the navigation using the tab selection.
            tabWizardControl.SelectTab(currentSelectedTab);
        }
    }
  

Comments

[JosephHirn]

You could use the TabControl.Selecting event, setting e.Cancel = true for the "disabled" tabs. The tabs won't actually appear to be disabled (greyed out) unless you paint them yourself, though. I would probably just remove the tabs altogether and add them as the user progresses through the quiz.

[gridtrak]

The comment to set e.Cancel = true in the TabControl.Selecting event works with a flicker as it displays the next tab then cancels and restores the previously selected tab.

[Oliver]

it tells me that 'object' does not contain a definition for enabled. :\

[Marius]

Cast it to msdn.microsoft.com/de-de/library/…

[Oliver]

which is not what should be happening.

[Oliver]

im starting to think that tabs cannot be disabled. plus according to msdn.microsoft.com/de-de/library/… Enabled does not serve any role with tabs.

[Jeff]

That's strange, as it works in Delphi (but thats VCL, not WinForms - oh well). How about hiding the tabs with .Visible = false;?

[mathgenius]

I advocate to remove this as the accepted answer as it clearly does not solve the problem AND it outright does not work, is completely incorrect and is sort of insulting that it was proposed as "something along these lines", despite it not being tested or even consulted with documentation (which says it's wrong).

[gridtrak]

This method triggers the TabControl_SelectedIndexChanged event when not wanting to change the tab. The advantage of this method is there is no flicker experienced when simply Cancelling the TabControl.Selecting event.